Tire tread shaping and truing machine



Sept. 2, 1941. P. E. HAWKINSON 2,254,526

TIRE TREAD SHAPING AND TRUING MACHINE Filed Feb. 21, 1949 4'Sheets-She et l Jnven for Y/ "21 27 PauZEHaWkz'nson By his Aflorne s Sept. 2, 1941. v P. E. HAWKINSON 2,254,526

TIRE TREAD SHAPING AND TRUING MACHINE Filed Feb. 21, 1940 4 She ets-Sheet 2 l;l lll' .bvvehior Paul Efiawkzhson v fly his flfiofpeys P. E. HAWKINSON 2,254,526

TIRE TREAD SHAPING AND TRUING MACHINE 4 Sheets-Sheet 3 Sept. 2, 1941.

Filed Feb. 21, 1940 so. T 52% 57 52 K 54 45 4a 38 41 A? 5 51 vs zrenior Paul E Haw/ 2773022 5y Jr's Afiornegs M MW/Mw Sept. 2, 1941.

P. E. HAWKINSON TIRE TREAD SHAPING AND TRUING MACHINE 4 sheets-sheet 4 F'ilg i Feb. 21, 1940 jln fen io Paul E H0 wkinsan .B

= y 171'; Aiiome v Patented Sept. 2, 1941 FiCE' I 'rms ramp SHAPING AND TRUING MACHINE Paul E. Hawkinson, Minneapolis, Minn., asslgnor to Paul E. Hawkinson Company,'Minneapolis, Minn., a corporation of Minnesota Application February 21, 1940, Serial 320,125

Claims.

My present invention provides an improved machine or machine for shaping and truing up the worn treads ofpneumatic-tire casings preparatory to application of additional tread ma terial and, generally stated, consists of the novel devices, combinations of devices, and arrangement of parts hereinafter described and defined in the claims.

It is a well-known fact that commercial tire casings under road wear are worndow'n in a manner that leaves a relatively flat worn groundengaging surface with annular'shoulders at the opposite sides or edges thereof. This worn surface is usually slightly convex' transversely of the casing.- 'but is vrelatively flat as compared with the interior of the casing. Also, this worn tread surface in a worn casing will usually be somewhat irregular and will require truing up or re-forming to some extent. for the proper application of retread rubber, and it has 'been the common practice to true-up, smooth up and condition the worn surface for the application of the retread rubber by what is known as a bufling action usually produced by a buiilng wheel having a barbed or more or less abrasive cutting face. In producing the bufllng action, the relatively flat but slightly convex worn surface of the" tire should be bufied oil and trued up on the proper transverse arc or curve and which are or curve will vary largely according proved bufllng machine and the bufling wheel, looking at Fig. 1 from the right toward the left;

Fig. 3 is a vertical section taken approximately on the line Hgof Fig. 1, some parts 1lieing broken away and some parts being shown full; r Fig. 4 is a view in perspective showing the bufling machine looking at the same from the rear in respect toFig. 1; v

Fig. 5 is a .view in perspective corresponding closely to, Fig. 4 but looking. at the same on a slightly different angle and showing also a tire casing placed on the dummy wheel applied with the casing in position for bufling action the said wheel and easing being in transverse diametrical section;

Fig. 6' is a transverse section taken approximately on the line .6-6 of Fig. 5, some parts being broken away;

Fig. 7 is a fragmentary section taken on the line 'l-lof Fig. 4;

Fig. 8 is a' side elevation showing the base plate and lifting device of the niachirie, other part being removed; and s Fig. 9 is a view partly in side elevation with some parts sectioned on the line 9-9 of Fig. 5, various parts of the machine being removed.

The primary support of the machine shown is in the form of a base plate l5 which, at one to the transverse cross-section and' axial diameter of the casing, and to tire running pressure.

Generally stated, my invention has for its object to provide and does provide a bufilng machine or device, by the use of which the above indicated objects or requirements may be rapidly and accurately accomplished.

In the drawings of this application, I have illustrated a commercial machine embodying not only the bread or generic features of the invention, but certain other minor but important features, but it will be understood that this improved machine is capable of various modiflca" tions within the scope of the invention herein disclosed and broadly claimed. I

Referring to the drawings, wherein like characters indicate like parts throughout the several views: f

Fig. 1 is a plan view of the'improved machine showing the same in position for presenting a tire casing to a buffing wheel, some parts being broken away:

as journaled to lugs l1 rigidly projecting from the base plate. At its other end, the base plate is provided with a lifting devicewhich, as shown,

85' ends of lifting bars 19 intermediately pivoted,

includes (pastor-acting rollers 18 applied to the by a cross-shaft 20 to flanges 2| rigid on the base plate It. The free inner ends of the lifting bars 19 normally rest upon crank pins 22 of an eccentric shaft 23 journaled in the flanges 2| and provided with an extended arm 24, se

particularly Figs. 2 and 8-.

' i when lever 24 is moved, say about 180, from the wheels I! will be raised and that end of the base piate'will then be lowered onto lugs or projections 25 and said lugs will then hold the base plate and the machine against'accidental move- Fig. 2 is aview in perspective showing the imriient on the floor.

Rotatably mou nted on the base plate is a'tfiriitable 26. This tum-table is plvotally connected to the base plate by anaxial pivot bolt or pintle 21 and to make said table very easy to turn, a ball bearing device 2| is interposed between said turn-table and the base plate, as best shown in Fig. 6. To lock theturn-table in what is treated. as normal position, it is shown as provided with a lock bolt II, see particularly Fig. 7, the depending end cf which is engageable with'a seat 30 in the base plate. This lock bolt II is of a vertically movable type provided with a projecting pin 3i adapting the lock bolt to be lowered into the seat III or, by slight turning thereof. to t be locked upward in an inoperative position,

shown by dotted lines in Fig; 'l.

Secured to the tum-table, andrising therefrom on a line eccentric tothe axis of said turntable, is a strong upright column." that supports the chief elements of the machine. Mounted on the column 32 is a vertically adjustable head block 33 that is adapted to be vertically adjusted and-to be rigidlysecured on said col umn by suitable means, such as a set-screw or screws 34, shown in Fig. 1. a

Mounted so as to slide horizontally in the head a a hub I] with spokesll, a flanged rim II, and

block 88 is a slide ll which, as best shown in j Fig. 3, has dovetailed encasement with said head block. The horizontal sliding movements of this K slide SI and the set adjustments-thereof are arranged to be accomplished by means of a feedscrew it that has threaded engagementwith a nut-acting flange 81 of said head block and is swivelled to the lower end of an arm-like bracket ll, see particularly Fig. 2, that is bolted or other-' wise rigidly secured'to the adjacent end of said slide. The teed-screw 80 is thus swivelled to the slide and coupled for sliding movements therewith by means of spaced thrust collars ll pinned or otherwise rigidly secured to said feedscrew. At one end, the feed-screw ll is shown as provided with a hand wheel ll adapting it be easily manipulated.

Again, by reference particularly to Fig. 3, it will be noted that a non-rotary Sp dle 4| is rigidly secured to the slide, II and projects hori- 'otally connected toggle levers II and II, the latter of which is pivotally connected to lever II, and the former of which is pivoted at IT to the upper end of bracket "and is shown as Drbvided with a hand-piece II at one end and at its other end with an' oflse't lug II that limits the movement of the tussle to the position shown by dotted lines in Fig. 9. and in which dotted line position the toggle will-be on a dead center and will hold the retarding brake released.

The tire casinglis indicated by'the character Y. For. holding the .casing while it is being buiied, I provide a sort of a -dummywheel which will hold the tire casing substantially in the way that it wouldbeheld by-the rim ofa vehicle wheel. .This dummy wheel involves rim lock ring 03. The hub ll islnternally spllned so that it is adapted .to'be freely slid onto and oi! from the sleeve 43, and when applied thereto, will be rotated with the brake drum. 'Asim- -ple device is provided for'detachably locking the hub Cl, and hence, the dummy wheel and tire casing in definite position in respect to the brake zontally therefrom. Rotatably mounted on the spindle 4i, preferably by means of ball bearing devices 42, is a. drum-carrying sleeve 43, to one endoi' which a brake drum 44 is rigidly secured by suitable means, such as long splines 4] on the exteriorof said sleeve. This drum is thus conhected for rotation with the sleeve, but is not intended nor is it readily removable from said sleeve. The sleeve 43 is, by the ball bearing devices 42, made very freely rotatable on the spindle II but isheld against axial movements on said spindle.

. For co-operation with'the brake drum [4 isa shoe-acting brake band II which, at one end, is anchored to theslide N by means'oi' an anchoring pin 41, see particularly Fig; 9. The free end of this brake band 48 is, by a pin ll, anchored to an arm 48' which is connected to another arm it by means of a hub Ii pivoted on the spindle 4| between the slide II and the hub of brake drum H, see particularly Figs. 3 and 9. The pri-: mary brake-actuating arm II is connected by a coiled spring I! to an adiusting'screw II, see particularly Fig. 9, that slides freely through the upper end of arm-like bracket SI and has thread- I ed engagement with an adjusting sleeve I that is free for rotation and reacts against the head or upper end of said bracket ll. At this point. it is only necessary to state that when released, the tension of spring I! will set the brake b nd barbed'bllmnk band H of the detachable and drum. Themeans shown for this purpose involves a U-shaped bracket ll secured to the web of the brakedrum and a spring-projected latch bolt ll mounted for movements through the ends of the bracket 04.. The headllor-inner end of lock belt I is preferably beveled and is engageable with an annulangroove l1 formed in the hub ".1 with this arrangement the hub.

can be pressed against theQbrake-drum and the spring-pressed latch bolt will automatically engage in the groove 81, thereby locking the hub against-axial movements in respect to the drum. The p se of the annular lock groove 01 is to permit the casing-eq i ped dummy wheel to be slipped onto the sleeve and locked asainst axial movements, regardless of the position of rotation of the hub and the parts carried thereby. In Figs. 1 and 2,-there is shown a bumng wheel ll carried by a power-driven spindle ll Journaled ina fixed bearing II. This bufllng wheel I is shown as provided with a conventional replaceable type. I

Use and operation of the machine The bumng. wheel as will be driven in a 001mter-clockwise direction in respect'to Fig. 2 and under the bum s action, the tire casing and its supporting wheel wilLby the action of the bufling wheel. e Otated in a clockwise direction inrespect to said -view..' The frictional and cutting action of ,thebuii'ing wheel willtend to rotate the tire casing at the same peripheral speed as said bumnk wheel, but by settingthe frictional brake, the rotation of the: casing may be re-- tarded to any desired extent.

Obviously the tire casing will'be applied to its carrying wheel while the wheel is removed from the spindle and sleeve and thereafter the wheel with the casing will be telescoped on to the splined sleeve and pushed minst the brake drum M where it will be locked to the sleeve and drum 'by the latch ll. When the turn-table is then ads iusted, as shown by full lines in the drawings,

' surface-faith v a with theibufllng the medial plane of the casing will be in the medial vertical plane of the truck made up of the base plate It and its supporting rollers. By

The bearing head should be vertically ad-,, .iust d a he x s 9 5 h:sr ndleyil1yill -be. slisht y-:b l w eiho z talmlan I canoe-that; when the, turn tabe-and. tire arebsy Y I 1 I 0 '2. In a machine of the kind described, a sup- -tr n mins-t unte in melan n-E 24 turnetabl'e "is-'lockedwith theitirje' casing infth ntermediate-'position,, shown byf Y thetruck'should, then be moved heels ;so ;,as to. bring the tread substantially into. contact lines "in r1 raised soifiasto" dropthe base plate. it. onto the floorandf.thereby zanchor the machine against Thereafter, by manipulationg'of the feed-screw l6,- theslide I5 accidental slipping imovei'nents.

andthetire casingwill be advanced against the builln'gyheelflq y I It will" be noted that the spindle projects far beyond-the sleeve 43. so that it serves ,as a convenient handle for oscillating-the turn-table and,

the tire casing back and forth, as indicated'by dottedflines in Fig. 1. By thus oscillating the casing and progressively advancing the ,.same

against the boiling wheeL'the tread surface ,of the .tire may be very quickly and accurately-prepare'd'for the application of the tread rubber thereto. h I a l As above indicated, the speed at which the tire casing and its supporting wheel will be rotated by the frictional action of the lo'ufllng wheel may be varied simply by adjustment of the tension ofsaid spring; When it is desired to lock the brake in released position, it is only necessary to move 3 a s eat s. tha by manipula 1 'tion; or {their-m1 fli' lthe, truckfjwlfiaels u will. be

used as anefflcient tester for balancing the casing and making allowances for balance in the application of tread-rubber. For the release of the carrying wheelfrom the drum, it is only necessary to Dull outward on the latch 86..

v In accordance with the patent statutes I have disclosed a complete machine or device for the purposes had in view, but it will be understood that the same is capable of various modifications all within the scope of the invention .cioscd andbroadly claimed.

In 1 9; machine of'the .kind described, a supspindle-mounted thereon, a -s;leeve,rotatport provided with a projecting spindle, a sleeve iournaled on said spindle, a brake drum connected to said sleeve for rotation therewith, a frictional brake element acting on said drum to retard the rotary movement of said sleeve, and a tire-casing carrying wheeldetachably applicable to said sleeve for rotation with said sleeve andbrakedrum.

-3. In a machine of the kind described, a support, a horizontally movable slide mounted on said support, a spindle projecting from said slide, 'a'sleeve iournale'd on said spindle, a brake drum connected to'said spindle for rotation therewith,

a brake shoe-acting element cooperating with said drum to retard the movement of said sleeve,

and a tire-casing carrying wheel detachably applicable to said sleeve for rotation with said sleeve and brake drum.

4. The structure defined in claim I in which i there is an adjustable yielding tension device applied to the brake mechanism for varying the frictional retarding action thereof.

5. The structure defined in claim 3 in further combination with a feed screw connected between said slide and its support when imparting feed movements to said slide and parts carried thereby.

.6. The structure defined in claim 1 in further combination with a. latch operative to detachably secure the rotary brake element tosaid wheel.

7. The structure definedin claim 1 in which the hub of saidwheel has an annular groove, and

the toggl-actlng-linkbl-W to the position indicated by dottedlines in Fig. Sand in which position the said toggle will be ona dead center and isrself-locking in.,that position. It is important that the brake band, when released, should ;beqcompletely--out of contact with the brake drum and this is accomplished when the toggle is set in dotted line position as above indicated.-

or course, the turn-table must be released from the base plate when the table and tire casing are to be oscillated; and this is quickly accomwhen the brake is released. the device can be the rotary element of said brake has a retractable latch engageable with said hub groove.

8. The structure defined in claim 2 in further combination with a retractable latch carried by said drum andengageable with the hub of said wheel to detachably connect said drum and wheel against axial movements.

9. In a machine of the kind described, an upright support, a bearing head on said support, a slide horizontally movable in said head. a spindle projecting from said slide, a sleeve iournaled on said spindle, and-a tire carrying wheel rotatable with but slidable axially onto and oil from said sleeve.

10. The structure defined in claim 9 in which said bearing head is vertically adjustable on said upright support, and in further combination with a manually operated feed-screw affording a connection between said slide and bearing head.

11. In a machine of the kind described, a base support, a turn-table pivotally mounted on said base support and provided with an upstanding herein dissaidF-"s ama-,9. "friction" brake operative Ethe;rotation of said; Sleeve, ,and .;a tires .s eeve -ahdfrotatabie :withthe rotary element of" post, a bearinghead on said post, a laterally pro- 1 jectingi-splndlelsllpp m' by said bearin: head and a tire casing supporting wheel journaled on' said spindle tor oscillatory movements on a vet-.-

tical axis that lies in the medial plane of said .124'Ihe structurede'fined in claim 11in which 'said-jspindle'iprojects and aiifordsxa handle by rneans or Whichsaid turn-table and partscarried ,therebywmay he oscillated.'

13. ha machine 0! the kind described, a hase support, a turnrtable pivotally mounted'on said 'base support and provided with an upstanding bearing post oilset iroxn'theaxis or the turn-table plvot',"1a; bearing headon the upper portion or.

said post, a slideyhorizontally movable in said jecting spindle, :a brake drum rotatable on said s'pindle, a" tire casingcarryinfi-wheel "slidahle onto said spindle, means for securing said wheel for rotation with said brake dri'im,E and frictional means co -operating with said brake tard'ithe movement thereof.

drum tore- 14. The structure defined in claim ism co binatlonwith' means for lockin: 'the'brake-acting element out attraction on saiddrumt said bearing head" is vertically adjustable on said t l V v 16. The structure dei'inedin claim 13 in which said'bearinz head is vertically adlustable'on said post, and a teed-screw aflord-ingia connection between said bearing head and slide tonnanually imparting teed'movernentsto said slidein'd carried thereby a, 17. In a 'r'nachineo! base support and provided 'withan ,upstandinl bearing post oilset rromcneuwor the'turnta'ble pivot. a'bearinkhead on theupper'portion 01 [said 'p'ost,a slide hbrizontallyvmovable'insaid head and provided with a laterally pro lectinz spindle, a sleeve rotatable on said-spindle,

said'spindle prolectin'z'beyond said sleeve to ati'ord a handletoroscillatingsald turn-table and reed rnovements 1a; The structure defined in claim 17 in further dental axial movements.

- 19. In a machine '0! thekind described," a base 4 mounted to oscillate on ahvertical'axis and having an upright'member oilset from said'lx'is, a

head vertically adjustablefon said 'pfllht meniber, a'slide horizontally movable on said head, and'means on said head for rotatively supportinl a tire casing with its medial plane positlonedto axis 01' said base.

include the pivotal PAUL"E.HAWK1NSON.

v the .nnualscnbeaasus v support, a' turn -table 'pivotally mountedon'sa'i'd 

